Green Tree, PA. -- After a six-year hiatus, the Pittsburgh Open returned March 25-27 and drew 139 competitors from across the country to the Radisson Hotel in suburban Green Tree Borough just outside of downtown Pittsburgh.

The open section of the tournament resulted in a three-way tie between two GMs - Alexander Onischuk, of Virginia, and Alexander Shabalov, of Pennsylvania -- and a young upsetter named Kevin Y. Cao, a 14-year-old middle schooler from St. Louis, Mo., who entered the open section ranked 12th but emerged as the third-highest rated player among the three top victors.

“It’s a very good win,” said Andrew Rea, assistant TD for the Continental Chess Association, in reference to Cao’s victory. “He’s not a titled player and he’s able to tie with two grandmasters.”

But Cao, sporting a green camouflage style St. Louis Cardinals cap, remained humble about his victory and sought to keep it in perspective.

“I didn’t play anybody (rated) over 2400,” noted Cao, who was rated at 2236 before the tournament. “They’re grandmasters and stuff,” he said of fellow top open winners Onischuk and Shabalov, who were rated 2764 and 2668, respectively, prior to the tournament.

Having drawn the first two games in the five-round tournament, Cao said he initially didn’t expect to win anything but ended up with four points after he won the last three games, including matches against WIM Iryna Zenyuk, of Pennsylvania, and FM Carl Brandon Boor, of Ohio.

Cao said he made the lengthy road trip to Pittsburgh with his father in order to earn a few points and get better at chess. He said wasn’t concerned with the prize money. In fact, the teenager left the hotel without collecting his $950 check. (which will be mailed to him.)

Onischuk, the 2006 U.S. Chess champion, and Shabalov both said they entered the Pittsburgh Open in order to prepare for the upcoming 2011 U.S. Chess Championship, which is set to take place next month in Cao’s hometown of Saint Louis.

Onischuk said he’s trying to reclaim his title.

“I’ve been preparing for the U.S. Championship for quite a long time,” Onischuk said,

Onischuck, whose son, Philip, age 6, competed in the under 1200 section and scored 1.5 points after he took a bye and got a draw, said he was glad the Pittsburgh Open returned and that he hoped the tournament sticks around for good.

Although the tournament drew competitors from as far away as Arizona and New York, Bill Goichberg, chief director of the tournament and president of the Continental Chess Association , said he was “slightly disappointed” with the turnout but said the association would nevertheless seek to hold another Pittsburgh Open around the same time next year.

Also see some games from the event, including Onischuk-Shabalov, which was added to this article on Monday night.